Brachos 31b: The Rebbe-Talmid Relationship

The gemara teaches that Shmuel was guilty of מורה הלכה בפני רבו - paskening a halacha in front of his Rebbe, Eli. Tosfos writes that even though he had not yet learned from him, nevertheless since Eli was gadol hador and Shmuel came to learn before him [בא לפניו ללמוד], it is considered that he paskened in front of his Rebbe. We must understand the combination of these two elements - Eli being gadol hador and Shmuel coming to learn before him.

It says in Devarim [5/ 24] that the Jewish people came before Moshe and insisted that he speak in the name of haShem. This was the "ksav rabbanus" of Moshe Rabbeinu where he was invited to be the Rebbe of Klal Yisrael. This pasuk was said in the context of maamad har sinai which is the paradigm of limmud hatorah for all generations. Thus, we have model for all of the future generations that a talmid must accept upon himself the guidance and leadership of his Rebbe.

After understanding this principle we can now shed new light on the explanation of Tosfos that "coming before him to learn" [בא לפניו ללמוד] is the litmus test of a true talmid. Even if a person learns a tremendous amount of Torah from someone else it is not yet subsumed under the category of true מסירת התורה. This is only accomplished when he is first מקבל upon himself that the other person should be his Rebbe. בא אצלו of Shmuel was the מעשה קבלה.

But this is not enough. We also need the Rebbe to pass the words of Torah to the talmid. It is true that בא אצלו creates a readiness to receive but we also need the Rebbe to be ready to give. That is why Tosfos adds that Eli was gadol hador. The מציאות of a gadol hador is one of giving Torah to others. This completed the Talmid-Rebbe relationship between Eli and Shmuel [and resulted in Shmuel being guilty of מורה הלכה בפני רבו].

[Maamarei Pachad Yitzchak on Sukkos 85 - See there further for an explanation as to why an amora is not allowed to argue with a tanna. See also the sefer Drashos Beis Yishai of HaGaon Rav Shlomo Fischer Shlita where he ROCKS on this topic.]